Field of the Invention
The present invention relates to illuminated signs, and more in particular to thin emergency and exits signs illuminated using cold cathode florescent lamps and/or LED light panels.
Previously proposed signage, particularly for emergency and exit signs have typically been manufactured for use with incandescent or regular florescent bulbs. As a result the signs are relatively bulky and not aesthetically pleasing. This is particularly true with regard to those fixtures that are in intended to operate as combination AC/DC fixtures which have battery backups and require large battery modules.
In recent years some attempts have been made to manufacture emergency and exit signs using LED lamps because of their reduced size. Such lamps are typically mounted in an elongated strip within the fixture. While these lamps permit a smaller frame to be used for the fixture, they suffer from the limitation that LED's, to date, are available only in limited in colors, namely red, green and amber. They are not yet available to produce white light. As a result, the contrast in the sign message and the background produced with such lamps is not entirely satisfactory.
Recently a new form of lamp has been developed called a cold cathode florescent lamp. This lamp is of known construction and is very thin relative to its length, typically being about 3/8 to 1/4 of an inch in diameter. These lamps produce white light and therefore have great flexibility in signage applications. They also have the advantage that they require relatively low power to operate.
In accordance with the present invention, an illuminated sign fixture is disclosed which is designed to use a cold cathode fluorescent lamp (CCFL) or, alternatively, an LED lamp depending upon the requirements of the user. The fixture is formed of two frame elements, at least one of which has a central opening for exposing a sign panel. The other of the frame elements can take one of several forms, depending upon the particular mounting application desired. In each case, however, the second frame element has a peripheral portion which is complementary to the peripheral portion of the first frame element surrounding the opening, with both of those peripheral portions being mirror images of each other. The inner faces of these peripheral portions of the two frame elements contain mirror image mounting means for mounting either a CCFL or LED strip between the frame elements. They also include a mounting arrangement for supporting between the frames the small electrical circuit boards used to control current flow to the lamps.
In one embodiment a mounting canopy is provided for securing the frame to a ceiling or vertical wall. The canopy may contain electrical control elements and/or battery backup for the CCFL or LED lamp system used in the frame.
In accordance with another aspect of the invention, a mounting channel arrangement is provided for supporting either the CCFL or the LED strip within the frame. The mounting channel is generally U-shaped and has a pair of spaced legs which define an opening therebetween. The channel is mounted between the frames by a frictional engagement of interrupted ribs on the frames and complementary grooves in the legs of the channel. The grooves receive the interrupted ribs and hold the channel frictionally within the frame, with the channel opening facing toward an edge of the sign within the frame. A CCFL is supported within the channel with a pair of spring clips. Alternatively, if an LED strip is used, the circuit board on which the strip is mounted is received in a pair of opposed internal grooves formed in the legs of the channel. The grooves and circuit board are dimensioned so that the board is held in place with a friction fit.
In another embodiment of the invention one of the frame members includes an integral canopy for supporting electrical controls and batteries if desired. The canopy is closed with a cover containing a Molex connector and is adapted to be mounted on an electric junction box cover by a keyhole and pin arrangement so that the Molex connection makes an automatic connection when the fixture is mounted.
It is therefore an object of the present invention to provide an illuminated sign which is a relatively thin structure that can contain the electrical controls and batteries for the sign.
Another object of the present invention is to provide an illuminated sign arrangement which can utilize either a CCFL or an LED strip as the source of light.
A still further object of the present invention is to provide a flexible lighting system suitable for use with two different light sources which is relatively simple to manufacture and assemble.